At first glance,
R.M.Wanzer's earliest known model appears to be a simple Wheeler
& Wilson's copy. However, the needle arm is powered by a Singer-style
v-shaped yoke. The shuttle type is also different, being a straight
race configuration. First patented in the UK in 1863, an overlocking
variant followed two years later.
Elgin County Museum.
photo - Nick Jonkman.